Deep mtDNA divergences indicate cryptic species in a fig-pollinating wasp

Background: Figs and fig-pollinating wasps are obligate mutualists that have coevolved for ca 90 million years. They have radiated together, but do not show strict cospeciation. In particular, it is now clear that many fig species host two wasp species, so there is more wasp speciation than fig speciation. However, little is known about how fig wasps speciate. Results: We studied variation in 71 fig-pollinating wasps from across the large geographic range of Ficus rubiginosa in Australia. All wasps sampled belong to one morphological species (Pleistodontes imperialis), but we found four deep mtDNA clades that differed from each other by 9–17% nucleotides. As these genetic distances exceed those normally found within species and overlap those (10–26%) found between morphologically distinct Pleistodontes species, they strongly suggest cryptic fig wasp species. mtDNA clade diversity declines from all four present in Northern Queensland to just one in Sydney, near the southern range limit. However, at most sites multiple clades coexist and can be found in the same tree or even the same fig fruit and there is no evidence for parallel sub-division of the host fig species. Both mtDNA data and sequences from two nuclear genes support the monophyly of the "P. imperialis complex" relative to other Pleistodontes species, suggesting that fig wasp divergence has occurred without any host plant shift. Wasps in clade 3 were infected by a single strain (W1) of Wolbachia bacteria, while those in other clades carried a double infection (W2+W3) of two other strains. Conclusion: Our study indicates that cryptic fig-pollinating wasp species have developed on a single host plant species, without the involvement of host plant shifts, or parallel host plant divergence. Despite extensive evidence for coevolution between figs and fig wasps, wasp speciation may not always be linked strongly with fig speciation

A systematic review of the relationship between behavioral and psychological symptoms (BPSD) and caregiver well-being

Background: Behavioural and psychological symptoms in dementia (BPSD) are important predictors of institutionalisation as well as caregiver burden and depression. Previous reviews have tended to group BPSD as one category with little focus on the role of the individual symptoms. This review investigates the role of the individual symptoms of BPSD in relation to the impact on different measures of family caregiver wellbeing. Methods: Systematic review and meta-analysis of articles published in English between 1980 and December 2015 reporting which BPSD affect caregiver wellbeing. Article quality was appraised using the Downs and Black Checklist (1998). Results: 40 medium and high quality quantitative articles met the inclusion criteria, 16 were suitable to be included in a meta-analysis of mean distress scores. Depressive behaviours were the most distressing for caregivers followed by agitation/aggression and apathy. Euphoria was the least distressing. Correlation coefficients between mean total behaviour scores and mean distress scores were pooled for 4 studies. Irritability, aberrant motor behaviour and delusions were the most strongly correlated to distress, disinhibition was the least correlated. Conclusion: The evidence is not conclusive as to whether some BPSD impact caregiver wellbeing more than others. Studies which validly examined BPSD individually were limited, and the included studies used numerous measures of BPSD and numerous measures of caregiver wellbeing. Future research may benefit from a consistent measure of BPSD, examining BPSD individually, and by examining the causal mechanisms by which BPSD impact wellbeing by including caregiver variables so that interventions can be designed to target BPSD more effectively

Behavioural and psychological symptoms in dementia and the challenges for family carers: systematic review

Background: Tailored psychosocial interventions can help families to manage behavioural and psychological symptoms in dementia (BPSD), but carer responses to their relative's behaviours contribute to the success of support programmes. Aims: To understand why some family carers have difficulty in dealing with BPSD, in order to improve the quality of personalised care that is offered. Method: A systematic review and meta-ethnographic synthesis was conducted of high-quality quantitative and qualitative studies between 1980 and 2012. Results: We identified 25 high-quality studies and two main reasons for behaviours being reported as challenging by family carers: changes in communication and relationships, resulting in ‘feeling bereft’; and perceptions of transgressions against social norms associated with ‘misunderstandings about behaviour’ in the relative with dementia. The underlying belief that their relative had lost, or would inevitably lose, their identity to dementia was a fundamental reason why family carers experienced behaviour as challenging. Conclusions: Family carers' perceptions of BPSD as challenging are associated with a sense of a declining relationship, transgressions against social norms and underlying beliefs that people with dementia inevitably lose their ‘personhood’. Interventions for the management of challenging behaviour in family settings should acknowledge unmet psychological need in family carers

Oncogenic K-Ras suppresses IP₃-dependent Ca²⁺ release through remodeling of IP₃Rs isoform composition and ER luminal Ca²⁺ levels in colorectal cancer cell lines

The GTPase Ras is a molecular switch engaged downstream of G-protein coupled receptors and receptor tyrosine inases that controls multiple cell fate-determining signalling athways. Ras signalling is frequently deregulated in cancer underlying associated changes in cell phenotype. Although Ca2+ signalling pathways control some overlapping functions with Ras, and altered Ca2+ signalling pathways are emerging as important players in oncogenic transformation, how Ca2+ signalling is remodelled during transformation and whether it has a causal role remains unclear. We have investigated Ca2+ signalling in two human colorectal cancer cell lines and their isogenic derivatives in which the mutated K-Ras allele (G13D) has been deleted by homologous recombination. We show that agonist-induced Ca2+ release from intracellular stores is enhanced by loss of K-RasG13D through an increase in the ER store content and a modification of IP3R subtype abundance. Consistently, uptake of Ca2+ into mitochondria and sensitivity to apoptosis was enhanced as a result of KRasG13D loss. These results suggest that suppression of Ca2+ signalling is a common response to naturally occurring levels of K-RasG13D that contributes to a survival advantage during oncogenic transformation

Exponential complexity of an adiabatic algorithm for an NP-complete problem

We prove an analytical expression for the size of the gap between the ground and the first excited state of quantum adiabatic algorithm for the 3-satisfiability, where the initial Hamiltonian is a projector on the subspace complementary to the ground state. For large problem sizes the gap decreases exponentially and as a consequence the required running time is also exponential.Comment: 5 pages, 2 figures; v3. published versio

On the Renormalization of the Kardar-Parisi-Zhang equation

The Kardar-Parisi-Zhang (KPZ) equation of nonlinear stochastic growth in d dimensions is studied using the mapping onto a system of directed polymers in a quenched random medium. The polymer problem is renormalized exactly in a minimally subtracted perturbation expansion about d = 2. For the KPZ roughening transition in dimensions d > 2, this renormalization group yields the dynamic exponent z* = 2 and the roughness exponent chi* = 0, which are exact to all orders in epsilon = (2 - d)/2. The expansion becomes singular in d = 4, which is hence identified with the upper critical dimension of the KPZ equation. The implications of this perturbation theory for the strong-coupling phase are discussed. In particular, it is shown that the correlation functions and the coupling constant defined in minimal subtraction develop an essential singularity at the strong-coupling fixed point.Comment: 21 pp. (latex, now texable everywhere, no other changes), with 2 fig

REMCARE : pragmatic multi-centre randomised trial of reminiscence groups for people with dementia and their family carers : effectiveness and economic analysis

Background Joint reminiscence groups, involving people with dementia and family carers together, are popular, but the evidence-base is limited. This study aimed to assess the effectiveness and cost-effectiveness of joint reminiscence groups as compared to usual care. Methods This multi-centre, pragmatic randomised controlled trial had two parallel arms: intervention group and usual-care control group. A restricted dynamic method of randomisation was used, with an overall allocation ratio of 1:1, restricted to ensure viable sized intervention groups. Assessments, blind to treatment allocation, were carried out at baseline, three months and ten months (primary end-point), usually in the person's home. Participants were recruited in eight centres, mainly through NHS Memory Clinics and NHS community mental health teams. Included participants were community resident people with mild to moderate dementia (DSM-IV), who had a relative or other care-giver in regular contact, to act as informant and willing and able to participate in intervention. 71% carers were spouses. 488 people with dementia (mean age 77.5) were randomised: 268 intervention, 220 control; 350 dyads completed the study (206 intervention, 144 control). The intervention evaluated was joint reminiscence groups (with up to 12 dyads) weekly for twelve weeks; monthly maintenance sessions for further seven months. Sessions followed a published treatment manual and were held in a variety of community settings. Two trained facilitators in each centre were supported by volunteers. Primary outcome measures were self-reported quality of life for the person with dementia (QoL-AD), psychological distress for the carer (General Health Questionnaire, GHQ-28). Secondary outcome measures included: autobiographical memory and activities of daily living for the person with dementia; carer stress for the carer; mood, relationship quality and service use and costs for both. Results The intention to treat analysis (ANCOVA) identified no differences in outcome between the intervention and control conditions on primary or secondary outcomes (self-reported QoL-AD mean difference 0.07 (-1.21 to 1.35), F = 0.48, p = 0.53). Carers of people with dementia allocated to the reminiscence intervention reported a significant increase in anxiety on a General Health Questionnaire-28 sub-scale at the ten month end-point (mean difference 1.25 (0.25 to 2.26), F = 8.28, p = 0.04). Compliance analyses suggested improved autobiographical memory, quality of life and relationship quality for people with dementia attending more reminiscence sessions, however carers attending more groups showed increased care-giving stress. Economic analyses from a public sector perspective indicated that joint reminiscence groups are unlikely to be cost-effective. There were no significant adverse effects attributed to the intervention. Potential limitations of the study include less than optimal attendance at the group sessions—only 57% of participants attended at least half of the intervention sessions over the 10 month period, and a higher rate of study withdrawal in the control group. Conclusions This trial does not support the clinical effectiveness or cost-effectiveness of joint reminiscence groups. Possible beneficial effects for people with dementia who attend sessions as planned are offset by raised anxiety and stress in their carers. The reasons for these discrepant outcomes need to be explored further, and may necessitate reappraisal of the movement towards joint interventions

Non-relativistic limit in the 2+1 Dirac Oscillator: A Ramsey Interferometry Effect

We study the non-relativistic limit of a paradigmatic model in Relativistic Quantum Mechanics, the two-dimensional Dirac oscillator. Remarkably, we find a novel kind of Zitterbewegung which persists in this non-relativistic regime, and leads to an observable deformation of the particle orbit. This effect can be interpreted in terms of a Ramsey Interferometric phenomenon, allowing an insightful connection between Relativistic Quantum Mechanics and Quantum Optics. Furthermore, subsequent corrections to the non-relativistic limit, which account for the usual spin-orbit Zitterbewegung, can be neatly understood in terms of a Mach-Zehnder interferometer.Comment: RevTex4 file, color figures, submitted for publicatio

Mobile learning for delivering health professional education (protocol)

© 2015 The Cochrane Collaboration.This is the protocol for a review and there is no abstract. The objectives are as follows: The objective of this review is to evaluate the effectiveness of mLearning educational interventions for delivering pre-registration and post-registration healthcare professional education. We will primarily assess the impact of these interventions on students knowledge, skills, professional attitudes and satisfaction